Highly-rated Celtic youngster Ryan Mullen has signed a three-year professional contract at the club, Football Insider can reveal.

Goalkeeper Mullen is regarded as one of the brightest young prospects to emerge from Parkhead in recent years after impressing for club and country.

A number of clubs in the English Premier League are understood to have shown an interest in luring the teenager away from Celtic, but Mullen has decided to pledge his long-term future to the Scottish champions.

Football Insider has an exclusive picture that shows Mullen putting pen to paper on a deal with the club on Thursday night.

The 16-year-old shot-stopper has caught the eye for Celtic in the UEFA Youth League games against Paris Saint Germain and Anderlecht this season and he has been singled out as one for the future by Bhoys boss Brendan Rodgers.

Mullen represents Scotland’s U17s and he was taken a year ahead to last year’s Under 17s European Championship final in Croatia as an U16.

The news will come as a massive boost to Celtic as they would be loathe to lose their best talent to the riches of the English Premier League.